Store named parameters in sorted lists instead of using maps.

lib/type_propagation/builder.dart

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 library kernel.type_propagation.builder;
 
 import '../ast.dart';
 import '../class_hierarchy.dart';
 import '../core_types.dart';
 import 'canonicalizer.dart';
 import 'constraints.dart';
@@ skipping 1818 matching lines @@
 
   int visitFunctionType(FunctionType node) {
     // TODO: Handle arity range.
     int arity = node.positionalParameters.length;
     int function = builder.functionValueNode;
     for (int i = 0; i < node.positionalParameters.length; ++i) {
       int field = fieldNames.getPositionalParameterField(arity, i);
       int argument = environment.getLoad(function, field);
       visitContravariant(node.positionalParameters[i], argument);
     }
-    node.namedParameters.forEach((String name, DartType type) {
-      int field = fieldNames.getNamedParameterField(arity, name);
+    for (int i = 0; i < node.namedParameters.length; ++i) {
+      var parameter = node.namedParameters[i];
+      int field = fieldNames.getNamedParameterField(arity, parameter.name);
       int argument = environment.getLoad(function, field);
-      visitContravariant(type, argument);
-    });
+      visitContravariant(parameter.type, argument);
+    }
     int returnVariable = visit(node.returnType);
     environment.addStore(
         function, fieldNames.getReturnField(arity), returnVariable);
     return function;
   }
 
   /// Equivalent to visiting the FunctionType for the given function.
   int buildFunctionNode(FunctionNode node) {
     int minArity = node.requiredParameterCount;
     int maxArity = node.positionalParameters.length;
@@ skipping 73 matching lines @@
   visitFunctionType(FunctionType node) {
     int minArity = node.requiredParameterCount;
     int maxArity = node.positionalParameters.length;
     for (int i = 0; i < node.positionalParameters.length; ++i) {
       int argument = visitCovariant(node.positionalParameters[i]);
       for (int arity = minArity; arity <= maxArity; ++arity) {
         int field = fieldNames.getPositionalParameterField(arity, i);
         environment.addStore(input, field, argument);
       }
     }
-    node.namedParameters.forEach((String name, DartType type) {
-      int argument = visitCovariant(type);
+    for (var parameter in node.namedParameters) {
+      int argument = visitCovariant(parameter.type);
       for (int arity = minArity; arity <= maxArity; ++arity) {
-        int field = fieldNames.getNamedParameterField(arity, name);
+        int field = fieldNames.getNamedParameterField(arity, parameter.name);
         environment.addStore(input, field, argument);
       }
-    });
+    }
     for (int arity = minArity; arity <= maxArity; ++arity) {
       int returnLocation =
           environment.getLoad(input, fieldNames.getReturnField(arity));
       visitContravariant(node.returnType, returnLocation);
     }
   }
 
   /// Equivalent to visiting the FunctionType for the given function.
   void buildFunctionNode(FunctionNode node) {
     int minArity = node.requiredParameterCount;
@@ skipping 13 matching lines @@
         environment.addStore(input, field, argument);
       }
     }
     for (int arity = minArity; arity <= maxArity; ++arity) {
       int returnLocation =
           environment.getLoad(input, fieldNames.getReturnField(arity));
       visitContravariant(node.returnType, returnLocation);
     }
   }
 }